I'm now on my 3rd alternator because of bad luck with refurbed units. I installed the 3rd one this morning and it is putting out 12v+, however my car wont turn over and the boost reading on the Commander says +.64.....even when the car is turned off.

I tried to unplug the boost sensor and the PFC reads +2.14...even unplugged, WTF. My car seemed to be running fine before the need for the new alternator and rough when the alternators failed (below 11.5v). When i try to turn it over it sputters and sounds like **** but never actually starts. Im leaning more towards the PFC or electrical system as my problem and not so much the engine its self but i could be wrong.

Any ideas as to why the PFC is suddenly reading wrong? Or has anyone experienced a similar problem before? Where to start?

Jason

 

The PFC is reading boost, its too rich, it wont start. Either you have a short or the map sensor is toast. How are your other sensors reading like tps, omp, etc., normal?

thewird

 

did the PIM scale/ offset settings get changed from normal to option1. option2 etc???

Some have done this on accident playing with the comander.

Do you have a 2 or 3 bar map sensor?

 

Stock map sensor... what do I do from here?

 

Not a clue on how to check those sensor functions. Can you please tell me how?

 

From the main screen on the commander go to "settings/etc" then "sensor check". If anything is highlighted then the PFC isn't reading it. Typically if the MAP sensor isn't reading correctly your TPS sensors will be highlighted in the sensor check screen, this would indicate a failure within the PFC more than likely.

 

Could be a short in the wiring too.

thewird

 

Do these help?

 

True. I only mentioned the TPS sensors because internally the PFC has a 5v regulator that is shared on MAP and TPS sensor circuit. If all 3 sensors are out of range or not being read then its likely the regulator went bad.

No sensors are highlighted so I doubt the issue is the PFC. Double check that you didn't accidentally change your MAP sensor calibration to another option (there are 5 pre programmed within the PFC). Also, check the obvious- make sure the MAP sensor is connected to a hose to the manifold.

If everything checks out, then I would suspect either the MAP sensor is bad or the wiring for it.

 

Great feedback guys.

I found that my PIM voltge was set to program 2 instead of "normal". I must of accidentally set it to another PIM setting and when I set it to normal, then BAM. Started right up :0. I think there is some minor calibration issues i need to correct as was stated by Turbo8 because now in the start postion the boost is reading -54. At least she's runnin again